Degreasing apparatus



Nov. 26, 1963 E. .o. ROEHL DEGREASING APPARATUS Filed July 3, 1961 2 Sheets-sheaf. 1

5 mm TE m r w r M a w E Nov. 26, 1963 E. o. ROEHL DEGREASING APPARATUS 2 Sheets-Sheet 2 Filed July 5, 1961 INVENTOR. fie/v55 7' 0 E E/#- W 8 477'OE/VEXS United States Patent 3,111,952 DEGREASIN G APPARATUS Ernest 0. Roehl, Los Altos, Calif., assignor, by mesne assrgnments, to Baron Industries, Los Angeles, Calif, a corporation of California Filed July 3, 1961, Ser. No. 121,691 1 Claim. (Cl. 134-105) This invention relates to degreasing apparatus, and included in the objects of this inventionare:

First, to provide a degreasing apparatus in which the workpieces are not only exposed to vapors of a cleaning solvent, but are also subjected to a washing action of of the liquid solvent produced by condensing the solvent in a region above the lworkpieces and causing the liquid solvent to rain downward thereover.

Second, to provide a degreasing apparatus wherein the condensing means to effect washing of the workpieces is supported by the cover of the vat or container for the solvent and the workpieces, and is utilized in conjunction with a second condensing means lining the upper portion of the vat. More particularly, the cover supported condensing means is disposed below the wall mounted condensing means to constitute the main condenser when the cover is closed, whereas when the cover is open the wall mounted condensing means serves to prevent or minimize escape of solvent vapors, and the cover mounted condensing means quickly drains any residual liquid back into the vat.

Third, to provide a degreasing apparatus wherein the vat may be elongated and partly covered so that a conveyor may move workpieces into one end of the vat, then along the vat under the partial cover, and then upward and out of the vat; and wherein a condensing means is located under the partial cover to rain liquid solvent over the workpieces.

With the above and other objects in view, as may appear hereinafter, reference is directed to the accompanying drawings in which:

FIGURE 1 is a perspective view of the degreasing, apparatus showing the cover in a raised position;

FIGURE 2 is an enlarged, transverse, sectional view thereof taken through 22 of FIGURE 1, showing the cover in its closed position;

FIGURE 3 is an enlarged, fragmentary, bottom view of the drip wall employed to produce a rain of liquid solvent;

FIGURE 4 is a fragmentary, sectional view thereof taken through 44 of FIGURE 3.

FIGURE 5 is a substantially diagrammatical, longitudinal, sectional view of a modified form of the degreasing apparatus so arranged that workpieces may be moved by a conveyor therethrough.

The degreasing apparatus includes an outer shell 1 and an inner shell 2 between which may be packed insulation 3. The outer shell 1 is in the form of a rectangular box, the front side of which may be disposed at an angle and arranged to receive a control panel 4.

The inner shell 2 forms a vat chamber 5 open at its upper side. A suitable heater 6, preferably an electrical heater, is disposed under the inner shell 2. The side walls of the inner shell 2 are provided, near the open upper end of the vat chamber 5, with a condenser coil 7, through which water or other coolant is circulated.

A cover 8 is provided which may have sheet metal walls separated by insulation 9. The cover 3 is joined to the backside of the outer shell 1 by a hinge 10.

Supported from the underside of the cover 8 is a rectangular mounting structure 11 dimensioned to fit within the inner shell 2 and having a vertical dimension so 3,1 1 1,952 Patented Nov. 26, 1963 that its bottom wall 12 is disposed in a plane below the condenser coil 7.

The mounting structure 11 receives a second condenser coil 13 which overlies the bottom wall 12, and is adapted for the circulation of water or other coolant so as to chill the bottom wall 12.

The bottom wall 12 forms a drip wall, and for this purpose is provided with a multiplicity of downwardly directed projections 14 which may take various forms; for example, the projections may be small, semispherical in form. Each projection forms a focal point toward which liquid, condensing on the bottom wall 12, flows, collects, and then drips, as shown best in FIGURE 4.

Operation of the degreasing apparatus is as follows:

A quantity of conventional cleaning solvent, such as trichloroethylene or perchloroethylene, or chlorinated or fluorinated hydrocarbons, or other solvents commonly used for vapor degreasing or cleaning operations, is poured into the inner shell 2. Workpieces to be cleaned are placed above the liquid cleaning solvent on a rack 15.

The solvent is heated so that its vapors may circulate around the workpieces. When the cover 8 is open the condenser coil 7 chills the vapors as they rise in the inner shell 2 and condenses these vapors so that they do not flow from the top of the vat chamber 5.

When the cover 8 is closed, the bottom or drip Wall 12 becomes the primary condensing surface. The vaporized solvent as it condenses on the bottom wall 12 drains to the individual projections 14, and then drips or rains downwardly therefrom over the workpieces, so that the workpieces are washed with liquid solvent as well as treated by the vaporized solvent.

When the cover 8 is raised, the condenser 7 automatically takes over the function of condensing the vapor, and any residual liquid solvent remaining on the bottom wall 12 readily drains into the vat chamber 5 at the backside thereof.

If the cover 8 is left open for a short time before removing the workpieces, any residual liquid solvent is quickly evaporated for later condensation by the coil 7.

Reference is now directed to FIGURE 5. The construction here illustrated includes an elongated insulated box structure 16 forming an elongated vat chamber 17. In this arrangement, the bottom of the vat is provided with an immersion heater 18 which is covered with the liquid solvent.

As in the first described structure, a condenser coil 19 is mounted on the walls of the vat chamber 17 near its top or open side.

The top side of vat chamber 17 is partially closed by a cover 20 corresponding to the cover 8. The cover 20 may be fixed or hinged. The cover 20 is provided With a bottom wall 21 having projections corresponding to the projections 14, and a condenser coil 23 is positioned to chill the bottom wall 21 in the manner of the first described structure so that liquid solvent rains from the projections.

The ends of the vat chamber 17 are open so that a conventional conveyor 24 carrying workpieces 25 may travel downward into the vat chamber 17, then along the under side of the cover 20, and then upwardly and out the other end of the vat chamber 17.

Operation of the construction shown in FIGURE 5 is essentially the same as in FIGURES 1 through 4. The condenser coil 19 prevents escape of solvent from the open ends of the vat chamber 17. The condensing surface or bottom wall 21 is disposed low enough that it is contacted by the solvent in vapor phase so as to condense the vapor and cause the liquid solvent to wash the underlying workpieces.

While particular embodiments of this invention have been shown and described, it is not intended to limit the same to the exact details of the constructions set forth, and it embraces such changes, modifications, and equivalents of the parts and their formation and arragement as come within the purview of the appended claim.

What is claimed is: An apparatus for degreasing workpieces, comprising: a. a vat open at its upper side and adapted to contain a vaporizable liquid cleaning solvent and workpieces to be cleaned; b. means for vaporizing the cleaning solvent contained in said vat; c. a cover hinged to the upper side of said vat; d. a first condenser mounted on the side walls of said vat above the workpieces, said condenser operable when said cover is open, to condense the cleaning solvent and minimize escape of vapor from the vat;

e. and a second condenser carried by the underside of said cover and adapted on closure of said cover to occupy a position above the workpieces and below the region at which condensation takes place by action of said first condenser, whereby said second condenser on closure of said cover supersedes said first condenser;

. said second condenser including a multiplicity of downwardly directed projections, each forming a focal point for condensation of the cleaning solvent and causing the liquid cleaning solvent to drip onto the workpieces below.

References Cited in the file of this patent UNITED STATES PATENTS 1,771,698 Wolff July 29, 1930 1,875,937 Savage Sept. 6, 1932 2,273,939 Darnmers Feb. 24, 1942 2,732,322 Murray Jan. 24, 1956 

